<?xml version="1.0"?>
<!--
    * Licensed to the Apache Software Foundation (ASF) under one
    * or more contributor license agreements.  See the NOTICE file
    * distributed with this work for additional information
    * regarding copyright ownership.  The ASF licenses this file
    * to you under the Apache License, Version 2.0 (the
    * "License"); you may not use this file except in compliance
    * with the License.  You may obtain a copy of the License at
    * 
    *   http://www.apache.org/licenses/LICENSE-2.0
    * 
    * Unless required by applicable law or agreed to in writing,
    * software distributed under the License is distributed on an
    * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
    * KIND, either express or implied.  See the License for the
    * specific language governing permissions and limitations
    * under the License.    
-->

<document>

  <body>
  
  <section name="BCEL">
  <p>
    The Byte Code Engineering Library (Apache Commons BCEL&#x2122;) is intended to give users a
    convenient way to analyze, create, and manipulate (binary)
    Java class files (those ending with .class). Classes are
    represented by objects which contain all the symbolic information
    of the given class: methods, fields and byte code instructions, in
    particular.
  </p>
  
  <p>
    Such objects can be read from an existing file, be transformed
    by a program (e.g. a class loader at run-time) and written to a file again. 
    An even more interesting application is the creation of classes from scratch 
    at run-time. The Byte Code Engineering Library (BCEL) may be also useful 
    if you want to learn about the Java Virtual Machine (JVM) and the format of 
    Java .class files. 
  </p>
  
  <p>
    BCEL contains a byte code verifier named JustIce, which usually
    gives you much better information about what's wrong with your
    code than the standard JVM message.
  </p>

  <p>
    BCEL is already being used successfully in several projects such
    as compilers, optimizers, obsfuscators, code generators
    and analysis tools. Unfortunately there hasn't been much development
    going on over the past few years. Feel free to help out or you
    might want to have a look into the ASM project at objectweb.
  </p>

  </section>
  
  </body>
</document>
